OpenVMS Cluster Systems - OpenVMS Systems - HP

1.4 Communications
Introduction to OpenVMS Cluster System Management
1.4 Communications
The System Communications Architecture (SCA) defines the communications
mechanisms that allow nodes in an OpenVMS Cluster system to cooperate. It
governs the sharing of data between resources at the nodes and binds together
System Applications (SYSAPs) that run on different Alpha and VAX computers.
SCA consists of the following hierarchy of components:
Communications
Software Function
System applications
(SYSAPs)
System Communications
Services (SCS)
Consists of clusterwide applications (for example, disk and tape class
drivers, connection manager, and MSCP server) that use SCS software for
interprocessor communication.
Provides basic connection management and communication services,
implemented as a logical path, between system applications (SYSAPs) on
nodes in an OpenVMS Cluster system.
Port drivers Control the communication paths between local and remote ports.
Physical interconnects Consists of ports or adapters for CI, DSSI, Ethernet (10/100 and Gigabit),
ATM, FDDI, and MEMORY CHANNEL interconnects.
1.4.1 System Communications
Figure 1–1 shows the interrelationships between the OpenVMS Cluster
components.
Introduction to OpenVMS Cluster System Management 1–5